593116 - Use -fomit-frame-pointer when compiling jsinterp.c

Status: RESOLVED FIXED

(Firefox Build System :: General, defect)

Description

[Justin Lebar (not reading bugmail)]

js/src/Makefile.in explicitly sets the flags for jsinterp.c to

  -O3 -fstrict-aliasing

when using GCC.  But the MODULE_OPTIMIZE_FLAGS are set to

  -O3 -fstrict-aliasing -fomit-frame-pointer $(MOZ_OPTIMIZE_SIZE_TWEAK),

which seems much better.

Comment 1

[Justin Lebar (not reading bugmail)]

I may fix this in Bug 592923, unless there are objections.

Comment 2

[Justin Lebar (not reading bugmail)]

Fix up in bug 592923.

Comment 3

[Justin Lebar (not reading bugmail)]

Attachment: Patch v1

Here's the stand-alone patch for this that I probably should have written in the first place.

Comment 4

[[e-mail]]

dvander measured and said this *might* be a 1-2% win on V8.

Comment 5

[Kyle Huey (Exited; not receiving bugmail, old account, do not use)]

What does "might" mean?

Comment 6

[Justin Lebar (not reading bugmail)]

(In reply to comment #5)
> What does "might" mean?

Probably that there's too much variance to really tell.

I'm pushing to try now.

Comment 7

[[e-mail]]

(In reply to comment #5)
> What does "might" mean?

Statistical significance.

Comment 8

[Justin Lebar (not reading bugmail)]

I'm happy to land this if we get approval.

Comment 9

[(not currently active) Ted Mielczarek]

Comment on attachment 474140 [details] [diff] [review]
Patch v1

I think I ignored this because you had it patched elsewhere, but this is good.

Comment 10

[Justin Lebar (not reading bugmail)]

This looks good on try.

Comment 11

[Justin Lebar (not reading bugmail)]

http://hg.mozilla.org/mozilla-central/rev/19b83a1f22db